The present invention relates to improvements in or relating to switching devices, and is more particularly concerned with a method of adjusting bandwidth in such devices.
Traffic volume in the Internet is growing exponentially, doubling every three to six months. The current capacity of Internet Protocol (IP) routers is insufficient to meet this demand and hence products that can route IP traffic at extremely large aggregate bandwidths of the order of 10 Gbit/s to several Tbit/s. Such routers are termed “Super Routers”.
Additionally, there is a growing need to support multicast (one to many or many to many) communications within the internet or any other IP based network. To support such a service, an IP router must be able to replicate packets and send them to multiple outputs on a per packet basis. In a router where bandwidth allocations are strictly controlled (in order to support Quality of Service criteria), it is necessary to determine how much bandwidth to allocate to multicast traffic across the core switching fabric.